Route reliability record
MCO→IAH
Orlando to Houston
- Flights
- 3,670
- Period
- July 2025 to June 2026
- Distance
- 854 mi
- Carriers
- 3
This route lands a B+, 4 points better than the national rate of 77.6%. About one flight in six arrive 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 3,670 flights, of which United Airlines flew 2,472 at 84.1% on time.
United Airlines is the most reliable of the three carriers covered here at 84.1% on time across 2,472 flights.
Key figures
On time
82.0%
Arrivals under 15 minutes late, of 3,630 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
0.95%
National rate is 1.81%
Best carrier
United
84.1% on time across 2,472 flights
These figures cover 3,670 flights between July 2025 and June 2026. The median arrival is 14 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Which airline is most reliable on MCO to IAH
The choice of carrier is not cosmetic here. United Airlines arrives on time 84.1% of the time; Spirit Airlines manages 74.3%. Sample sizes sit next to every figure, because a two-point gap across 662 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 2,472 | 84.1% | 89 min | 0.65% | B+ |
| Frontier Airlines | 536 | 82.2% | 74 min | 0.37% | B+ |
| Spirit Airlines | 662 | 74.3% | 71 min | 2.57% | C |
United leads Spirit by 10 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 22 points, against 10 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am639 flights92.1%
- 8am–11am622 flights86.1%
- 11am–2pm637 flights91.3%
- 2pm–5pm687 flights78.9%
- 5pm–8pm830 flights70.4%
- 8pm–5am255 flights69.8%
Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 92.1% of the time, against 69.8% for the overnight window. That is 22 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 830 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 22 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 68.6% on time, 22 points below September, the best at 91.0%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. March was the busiest month here, with 366 flights.
Across the week, Tuesday is the strongest day at 86.9% on time and Sunday the weakest at 75.6%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 54,000 reported delay minutes.
- 35%Late-arriving aircraft
- 29%National Airspace System
- 27%Carrier
- 9%Extreme weather
- 0%Security
35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 54,000 reported delay minutes here, that single category outweighs weather by 4 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 53,692 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 92.1% on time here.
Cancellations sit at 0.95% against a national 1.81%, which is ordinary. Diversions add another 0.14%.
Connections and stage length
What a delay here actually costs
7.9% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route are the an hour and a half kind, which a normal layover absorbs.
The 854 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 81.6% on time across 3,669 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 3,670 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 91.0% on time and July 68.6%, a swing of 22 points. If the dates move at all, move them out of July before you think about anything else. 3,630 completed flights over 12 months sit behind that.
Common questions
MCO to IAH questions
How often is MCO to IAH delayed?
About one flight in six arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 18.0% of the 3,670 flights in this analysis, against 22.4% nationally. Delayed flights are late by an hour and a half on average.
Which airline is most reliable on MCO to IAH?
United Airlines leads at 84.1% on time across 2,472 flights. Spirit Airlines is at the other end on 74.3%, a gap of 10 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on MCO to IAH?
The 5am–8am departure window is the strongest at 92.1% on time. The 8pm–5am window is the weakest at 69.8%, 22 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on MCO to IAH?
July is the weakest month at 68.6% on time, compared with 91.0% in September. Across the year that is 22 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- IAH to MCO — the return legseparate record
- Orlando International (MCO) delay statistics
- George Bush Intercontinental (IAH) delay statistics
- United Airlines on-time record84.1%
- Frontier Airlines on-time record82.2%
- Spirit Airlines on-time record74.3%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. MCO to IAH and IAH to MCO are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.